How is Multithreading achieved in Python?

Python programming has a multi-threading package that can be used if one wants to multi-thread to speed their code up.

A construct called the Global Interpreter Lock (GIL) is available in Python. It is the work of the GIL to make sure that only one of the ‘threads’ can execute at any one point of time. Normally a thread accepts the GIL, does a little work, then passes it on the GIL to the next thread.  All this happens very quickly that will seem so to the human eye and it may seem like your threads are executing in parallel, but they are really just taking turns using the same CPU core. All this GIL passing adds overhead to execution. This means that if you want to make your code run faster then using the threading package often isn’t a good idea.